π€ AI Summary
In real-world scenarios, acquiring clean full-observation samples is prohibitively expensive, whereas noisy or partial observations are readily available. This paper addresses the problem of recovering the underlying data distribution from a black-box degradation process, given only a few clean samples and abundant noisy/sparse observations. We propose an EM-style iterative framework grounded in one-sided entropy-optimal transport and design a Stochastic Forward-Backward Deconvolution (SFBD) bridge modelβa generalized bridge formulation that, for the first time, extends bridge modeling to arbitrary black-box degradations beyond Gaussian noise. We establish a theoretically grounded, verifiable criterion for distribution recoverability and introduce a test-time adaptive calibration mechanism. Extensive experiments across multiple benchmarks and heterogeneous measurement settings demonstrate consistent, state-of-the-art performance in PSNR, SSIM, and other metrics, validating the efficacy and robustness of few-shot guidance for large-scale distribution recovery.
π Abstract
In many real-world scenarios, obtaining fully observed samples is prohibitively expensive or even infeasible, while partial and noisy observations are comparatively easy to collect. In this work, we study distribution restoration with abundant noisy samples, assuming the corruption process is available as a black-box generator. We show that this task can be framed as a one-sided entropic optimal transport problem and solved via an EM-like algorithm. We further provide a test criterion to determine whether the true underlying distribution is recoverable under per-sample information loss, and show that in otherwise unrecoverable cases, a small number of clean samples can render the distribution largely recoverable. Building on these insights, we introduce SFBD-OMNI, a bridge model-based framework that maps corrupted sample distributions to the ground-truth distribution. Our method generalizes Stochastic Forward-Backward Deconvolution (SFBD; Lu et al., 2025) to handle arbitrary measurement models beyond Gaussian corruption. Experiments across benchmark datasets and diverse measurement settings demonstrate significant improvements in both qualitative and quantitative performance.